LPR Walk Through / Tutorial

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Pulling my weight

I documented (link below) one LPR solution that I came up with from reading multiple LPR posts here. While it's not comprehensive it does have the essentials to get someone started for the price of a camera ($180) and about 6 hours of configuration / setup. My solution picks up about 650 license plates a week but a few times when I needed a plate due to suspected criminal activity the plates had been removed and/or covered.

Known around here

Here's a slice from a screenshot from last night (left some letters for you as this is my private car):

This is shot from a HFW5231-Z5, no zoom, from 25-30meters (that's almost 98 feet according to Google) with the settings mentioned above. Cam is "high" up. No additional lightning (there is almost no ambient light on our driveway), however cars drive at max 5km/u due to slope, bumps + curves.

n3wb

Night time image captures are a pain in the butt to configure but achievable. I recently purchased two Hikvision DS-2CD4A26FWD-IZH and one Vivotek panoramic and lets just say I have consumed a lot of coffee to get these to work at night along a highway. I have found trial and error is the only way forward as each application is different.

My biggest regret during planning is that I did not take the advice of others in this forum and get the camera with a better zoom. My initial goal was to capture license plates (no ALPR) and once I recovered from the substantial project cost, repurpose these units elsewhere. I was a bit skeptical as well that I could capture a 55+ mph moving vehicle. I am still fine tuning my settings, but it can be done. Good luck!

After having installed my own LPR system, my advice to a newcomer would be to consider buying a couple of Dahua SD49225T-HN cameras. The price differential over a good bullet camera (e.g. the Z12E) is only about $100 per camera, but the extra zoom combined with the ability to adjust the angle and direction without physically moving the camera might make it worthwhile.

Having issues with HFW5231E-Z12E. Those settings didn't work at all for me. I'm basically in pitch black area, no street lights on a gravel road. Of course auto focus is all jacked up ( don't understand how its that difficult for Dahua to fix)

Known around here

1/6 shutter will get you BLURRY plates for sure, unless cars are moving VERY slowly.
Most people end up ~1/1000th or shorter so as to minimize blur on moving plates.
the faster the cars are going, the shorter exposure you'll need...

camera megapixels is not so important, but you need 100 PPF or more to read plates, which is where the zoom comes in,
and PTZ certainly helps dial things in more easily. You also need different focus settings for night as IR refracts slightly differently than visible/white
light. Some lenses are better at compensating, but do so by splitting the difference so neither is perfect. Once you get the right
view and dial in the exposure to minimize blur, you may find you need more IR cuz it's just too dark.

Young grasshopper

1/6 shutter will get you BLURRY plates for sure, unless cars are moving VERY slowly.
Most people end up ~1/1000th or shorter so as to minimize blur on moving plates.
the faster the cars are going, the shorter exposure you'll need...

camera megapixels is not so important, but you need 100 PPF or more to read plates, which is where the zoom comes in,
and PTZ certainly helps dial things in more easily. You also need different focus settings for night as IR refracts slightly differently than visible/white
light. Some lenses are better at compensating, but do so by splitting the difference so neither is perfect. Once you get the right
view and dial in the exposure to minimize blur, you may find you need more IR cuz it's just too dark.